U.S. patent application number 13/956921 was filed with the patent office on 2015-03-19 for system for injecting fuel in a gas turbine combustor.
This patent application is currently assigned to General Electric Company. The applicant listed for this patent is General Electric Company. Invention is credited to Jonathan Dwight Berry.
Application Number | 20150076251 13/956921 |
Document ID | / |
Family ID | 52667065 |
Filed Date | 2015-03-19 |
United States Patent
Application |
20150076251 |
Kind Code |
A1 |
Berry; Jonathan Dwight |
March 19, 2015 |
SYSTEM FOR INJECTING FUEL IN A GAS TURBINE COMBUSTOR
Abstract
A combustion system uses a fuel nozzle with an inner wall having
a fuel inlet in fluid communication with a fuel outlet in a fuel
cartridge. The inner wall defines a mounting location for inserting
the fuel cartridge. A pair of annular lip seals around the
cartridge outer wall on both sides of the fuel outlet seals the
fuel passage between the fuel inlet and the fuel outlet.
Inventors: |
Berry; Jonathan Dwight;
(Simpsonville, SC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company |
Schenectady |
NY |
US |
|
|
Assignee: |
General Electric Company
Schenectady
NY
|
Family ID: |
52667065 |
Appl. No.: |
13/956921 |
Filed: |
September 19, 2013 |
Current U.S.
Class: |
239/418 |
Current CPC
Class: |
F23R 3/10 20130101; F23R
3/286 20130101 |
Class at
Publication: |
239/418 |
International
Class: |
F02C 7/22 20060101
F02C007/22 |
Goverment Interests
STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] This invention was made with Government support under
Contract No. DE-FC26-05NT42643-DOE awarded by the Department of
Energy.
Claims
1. A fuel nozzle assembly comprising: a fuel plenum, a fuel nozzle
outer wall, and a fuel nozzle inner wall, the fuel nozzle inner
wall defining a cartridge location and comprising a fuel plenum
inlet in fluid communication with the fuel plenum; and a fuel
cartridge comprising: a fuel cartridge outer wall, the fuel
cartridge outer wall comprising a fuel cartridge outlet in fluid
communication with the fuel plenum inlet when the cartridge is
inserted into the cartridge location; and annular lip seals
disposed around the cartridge outer wall, a first one of the lip
seals on one side of the fuel cartridge outlet and a second one of
the lip seals on a second side of the fuel cartridge outlet for
sealing the cartridge outer wall against the fuel nozzle inner wall
in a substantially gas tight fashion.
2. The fuel nozzle assembly of claim 1, wherein the fuel cartridge
comprises a plurality of cartridge compartments each containing
fuel.
3. The fuel nozzle assembly of claim 2, wherein a first cartridge
compartment is disposed around an axis of the cartridge and is
substantially cylindrical in shape.
4. The fuel nozzle assembly of claim 3, wherein a second cartridge
compartment is disposed between the cartridge outer wall and the
first cartridge compartment.
5. The fuel nozzle assembly of claim 4, wherein the first cartridge
compartment comprises a spray opening for spraying fuel into a
combustion chamber.
6. The fuel nozzle assembly of claim 5, wherein the fuel cartridge
outlet extends from the second cartridge compartment through the
cartridge outer wall.
7. The fuel nozzle assembly of claim 6, further comprising a
plurality of mixing tubes each for delivering a fuel and air
mixture to the combustion chamber, the mixing tubes each comprising
apertures therethrough in fluid communication with the fuel
plenum.
8. The fuel nozzle assembly of claim 6, wherein the first cartridge
compartment comprises a pressurized liquid fuel for spraying
through the spray opening and the second cartridge compartment
comprises a pressurized gaseous fuel for delivery through the fuel
cartridge outlet into the fuel plenum.
9. The fuel nozzle assembly of claim 8, wherein the liquid fuel
comprises an emulsified mixture of fuel oil and water, and wherein
the gaseous fuel comprises natural gas.
10. The fuel nozzle assembly of claim 8, wherein the fuel nozzle
outer wall is shaped to include a pair of mating surfaces such that
the mating surfaces of a plurality of fuel nozzles are placed
adjacent to each other to form a generally circular
arrangement.
11. A fueling system comprising: a fuel nozzle comprising: a fuel
plenum; a plurality of mixing tubes each for delivering an air/fuel
mixture through one end of the mixing tube, wherein the mixing
tubes are disposed substantially in parallel to each other, the
mixing tubes each comprising: a proximal end for receiving the air
which travels through the mixing tube, at least one fuel aperture
through a sidewall of the mixing tube in fluid communication with
the fuel plenum for receiving a fuel portion of the air/fuel
mixture that mixes with the air traveling through the mixing tube,
and a distal end comprising said one end of the mixing tube for
delivering the air/fuel mixture therethrough, and a fuel cartridge
chamber disposed substantially in parallel with the mixing tubes;
and a removable fuel cartridge inserted into the fuel cartridge
chamber, the fuel cartridge containing the fuel that mixes with the
air.
12. The fueling system of claim 11, wherein the fuel cartridge
comprises a first fuel compartment containing a liquid fuel, the
first fuel compartment comprising an opening at its distal end for
spraying the liquid fuel.
13. The fueling system of claim 12, wherein the fuel cartridge
further comprises: a second fuel compartment containing the fuel
that mixes with the air; and a fuel outlet extending from the
second fuel compartment through an outer wall of the fuel
cartridge, the fuel outlet in fluid communication with the fuel
plenum in the fuel nozzle when the fuel cartridge is inserted into
the fuel cartridge chamber.
14. The fueling system of claim 13, wherein the fuel cartridge
further comprises annular lip seals disposed circumferentially
along an outer wall of the fuel cartridge substantially in parallel
with each other, wherein a first one of the lip seals is disposed
on one side of the fuel outlet and a second one of the lip seals is
disposed on a second side of the fuel outlet for providing a
substantially gas tight seal between the outer wall of the fuel
cartridge and a wall of the fuel cartridge chamber.
15. The fueling system of claim 14, wherein the wall of the fuel
cartridge chamber comprises a pair of annular seal retention
projections each having a contour matching a contour of one of the
lip seals for sealingly mating therewith when the fuel cartridge is
inserted into the fuel cartridge chamber.
16. The fueling system of claim 13, wherein the fuel that mixes
with the air comprises natural gas and the liquid fuel comprises an
emulsion of fuel oil and water.
17. A fuel nozzle system comprising: a fuel nozzle comprising an
enclosed fuel plenum; a plurality of mixing tubes extending through
the fuel nozzle, the mixing tubes each comprising a first end in
fluid communication with an air supply and a second end for
delivering an air/fuel mixture, each of the mixing tubes comprising
apertures therethrough in fluid communication with the fuel plenum;
and a mounting tube extending through the fuel nozzle for receiving
and securing a removable fuel cartridge therein, the mounting tube
including an opening therethrough for establishing fluid
communication between an interior of the mounting tube and the fuel
plenum.
18. The fuel nozzle system of claim 17, further comprising: the
removable fuel cartridge received and secured in the mounting tube,
the removable fuel cartridge comprising: a gaseous fuel compartment
containing gaseous fuel in fluid communication with the fuel plenum
through an opening in an outer wall of the fuel cartridge and the
opening in the mounting tube; and a liquid fuel compartment
containing liquid fuel separate from the gaseous fuel and having a
nozzle for expelling the liquid fuel.
19. The fuel nozzle system of claim 18, further comprising: lip
seals disposed between the mounting tube and the removable fuel
cartridge, a first one of the lip seals on a first side of the
mounting tube opening and the opening in the fuel cartridge outer
wall, and a second one of the lip seals on a second side of the
mounting tube opening and the opening in the fuel cartridge outer
wall.
20. The fuel nozzle system of claim 19, wherein the mounting tube
comprises seal retention projections on an interior side of the
mounting tube for mating against the lip seals when the fuel
cartridge is inserted into the mounting tube.
Description
BACKGROUND OF THE INVENTION
[0002] The subject matter disclosed herein relates to fuel delivery
systems and more specifically, to fueling systems for gas turbine
combustors.
[0003] In general, gas turbines combust a mixture of compressed air
and fuel within a combustor to produce hot combustion gases. The
hot combustion gases rotate blades of the turbine to rotate a shaft
that drives a load, such as an electrical generator. Mixing tubes
within the combustor inject fuel and air into the combustor. In
some designs, the mixing tubes pre-mix the fuel and air before the
fuel and air enters the combustion zone. For example, the mixing
tubes may be employed to mix a gaseous fuel with air. However, the
fuel nozzles may not be designed to direct liquid fuel through the
mixing tubes. A separate liquid fuel supply is permanently
installed between the mixing tubes and sprays liquid fuel through a
nozzle into the combustor, while another fuel passage feeds gaseous
fuel into the mixing tubes. It is difficult to inspect internal
components of the combustion system because they are typically
enclosed in a sealed housing.
[0004] The discussion above is merely provided for general
background information and is not intended to be used as an aid in
determining the scope of the claimed subject matter.
BRIEF DESCRIPTION OF THE INVENTION
[0005] A combustion system uses a fuel nozzle with an inner wall
having a fuel inlet in fluid communication with a fuel outlet in a
fuel cartridge. The inner wall defines a mounting location for
inserting the fuel cartridge. A pair of annular lip seals around
the cartridge outer wall on both sides of the fuel outlet seals the
fuel passage between the fuel inlet and the fuel outlet. Advantages
that may be realized in the practice of some disclosed embodiments
of the multi-fuel cartridge system include easier inspection and
repair due to the removable cartridge, and less fuel tubes in the
air feed plenum to reduce air flow disruptions.
[0006] In one embodiment, a fuel nozzle assembly is disclosed which
includes a fuel plenum, a fuel nozzle outer wall, and a fuel nozzle
inner wall. The fuel nozzle inner wall defines a fuel cartridge
location and a fuel plenum inlet which is in fluid communication
with the fuel plenum. The fuel cartridge includes a fuel cartridge
outer wall having a fuel cartridge outlet in fluid communication
with the fuel plenum inlet when the cartridge is inserted into the
cartridge location. Annular lip seals are disposed around the
cartridge outer wall wherein a first one of the lip seals is on one
side of the fuel cartridge outlet and a second one of the lip seals
is on a second side of the fuel cartridge outlet. The lip seals
seal the cartridge outer wall against the fuel nozzle inner wall in
a substantially gas tight fashion.
[0007] In another embodiment, a fueling system is disclosed which
includes a fuel nozzle and a removable fuel cartridge. The fuel
nozzle includes a fuel plenum, a plurality of parallel mixing tubes
each for delivering an air/fuel mixture through an end of the
mixing tube, and a fuel cartridge chamber for securing the fuel
cartridge. Each of the mixing tubes have a proximal end for
receiving air, a fuel aperture through a sidewall for receiving
fuel, and a distal end for delivering the air/fuel mixture. The
fuel cartridge chamber is disposed substantially in parallel with
the mixing tubes and includes the removable fuel cartridge that
contains the fuel.
[0008] In another embodiment, a fuel nozzle system is disclosed
that includes a fuel nozzle with an enclosed fuel plenum. Mixing
tubes extend through the fuel nozzle, each including a first end in
fluid communication with an air supply and a second end for
delivering an air/fuel mixture. Apertures through the mixing tubes
are in fluid communication with the fuel plenum. A mounting tube
extends through the fuel nozzle for securing a removable fuel
cartridge and is in fluid communication with the fuel plenum.
[0009] This brief description of the invention is intended only to
provide a brief overview of subject matter disclosed herein
according to one or more illustrative embodiments, and does not
serve as a guide to interpreting the claims or to define or limit
the scope of the invention, which is defined only by the appended
claims. This brief description is provided to introduce an
illustrative selection of concepts in a simplified form that are
further described below in the detailed description. This brief
description is not intended to identify key features or essential
features of the claimed subject matter, nor is it intended to be
used as an aid in determining the scope of the claimed subject
matter. The claimed subject matter is not limited to
implementations that solve any or all disadvantages noted in the
background.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] So that the manner in which the features of the invention
can be understood, a detailed description of the invention may be
had by reference to certain embodiments, some of which are
illustrated in the accompanying drawings. It is to be noted,
however, that the drawings illustrate only certain embodiments of
this invention and are therefore not to be considered limiting of
its scope, for the scope of the invention encompasses other equally
effective embodiments. The drawings are not necessarily to scale,
emphasis generally being placed upon illustrating the features of
certain embodiments of the invention. In the drawings, like
numerals are used to indicate like parts throughout the various
views. Thus, for further understanding of the invention, reference
can be made to the following detailed description, read in
connection with the drawings in which:
[0011] FIG. 1 is a schematic flow diagram of an embodiment of a gas
turbine system that may employ fuel nozzles with multi-fuel
cartridges;
[0012] FIG. 2 is a cross-sectional view of the combustor of FIG.
1;
[0013] FIG. 3 is a cross-sectional view of an embodiment of a fuel
nozzle of the combustor of FIG. 1;
[0014] FIG. 4 is a cross section view of an embodiment of the fuel
nozzle that includes a multi-fuel cartridge; and
[0015] FIG. 5 is a cross section view of another embodiment of the
fuel nozzle that includes a multi-fuel cartridge.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The present disclosure is directed to fuel nozzles that
include multi-fuel cartridges. Each fuel nozzle may have a
segmented shape, such as a wedge shaped cross section, that allows
the fuel nozzle to fit together with adjacent fuel nozzles to form
an annular ring of fuel nozzles within a combustor of a gas
turbine. A series of mixing tubes are disposed within each fuel
nozzle to produce a fuel-air mixture that is directed to the
combustion zone. In particular, the mixing tubes direct air from an
air plenum mixed with fuel from a fuel plenum through the mixing
tubes to the nozzle face. The fuel plenum surrounds the mixing
tubes and gaseous fuel from the fuel plenum is directed into the
mixing tubes through apertures in the side of the tubes to produce
the fuel-air mixture. The fuel nozzles also may include a
multi-fuel cartridge that delivers the liquid fuel, such as fuel
oil or other distillates, and the gaseous fuel, such as natural
gas. Accordingly, the fuel nozzles described herein may provide the
flexibility to operate on liquid fuel, gaseous fuel, or a
combination thereof. The multi-fuel cartridge may be located within
the fuel nozzle between the mixing tubes. Accordingly, the liquid
fuel may be directed through the multi-fuel cartridge to the
combustion zone without flowing through the mixing tubes, and the
gaseous fuel may be directed through the mixing tubes to the
combustion zone.
[0017] The multi-fuel cartridge extends from the combustor front
end cover through the fuel/air plenums to the nozzle face. The
multi-fuel cartridge may be mounted within a cartridge holder tube
that secures the multi-fuel cartridge between the mixing tubes. The
multi-fuel cartridge includes an inner compartment, or passage, for
storing liquid fuel and a cartridge nozzle connected to the inner
compartment. The multi-fuel cartridge may also include one or more
outer compartments, or passages, for storing and directing gaseous
fuel to the mixing tubes. The multi-fuel cartridge may also include
air and/or water passages to direct air, water, or a combination
thereof, through the multi-fuel cartridge. The cartridge nozzle may
be located at the end of the multi-fuel cartridge to expel, or
spray, the liquid fuel into the combustion zone. According to
certain embodiments, the cartridge nozzle expels, or sprays, the
liquid fuel radially outward toward into the combustion zone. The
mixing tubes may be disposed radially around the multi-fuel
cartridge in a pattern designed to promote efficient mixing of the
gaseous fuel and the liquid fuel.
[0018] FIG. 1 is a block diagram of an embodiment of a gas turbine
system 10 that employs sector fuel nozzles that include multi-fuel
cartridges. The gas turbine system 10 may be part of a simple cycle
system or a combined cycle system. The gas turbine system 10
includes a combustor 12 that combusts fuel 14 to drive the gas
turbine system 10. According to certain embodiments, the fuel 14
may be a liquid or gaseous fuel, or a combination thereof, such as
natural gas, light or heavy distillate oil, naphtha, crude oil,
residual oil, or syngas.
[0019] Within the combustor 12, the fuel 14 may mix with
pressurized air 16, shown by arrows, and ignition may occur,
producing hot combustion gases 18 that power the gas turbine system
10. As discussed further below with respect to FIG. 2, the
combustor 12 includes sector fuel nozzles that pre-mix the gaseous
fuel 14 and the pressurized air 16 and direct the fuel-air mixture
into a combustion chamber in a suitable ratio for optimal
combustion, emissions, fuel consumption, and power output. Further,
the fuel nozzles also may include multi-fuel cartridges that direct
liquid fuel into the combustion chamber.
[0020] The pressurized air 16 includes intake air 20 that enters
the gas turbine system 10 through an air intake section 22. The
intake air 20 is compressed by a compressor 24 to produce the
pressurized air 16 that enters the combustor 12. The sector fuel
nozzles may direct the fuel 14 and the pressurized air 16 into the
combustion zone of the combustor 12 together with the liquid fuel
expelled from the multi-fuel cartridges. Within the combustion
zone, the pressurized air 16 combusts with the liquid and gaseous
fuel 14 to produce the hot combustion gases 18. From the combustor
12, the hot combustion gases 18 may flow through a turbine 26 that
drives the compressor 24 via a shaft 28. For example, the
combustion gases 18 may apply motive forces to turbine rotor blades
within the turbine 26 to rotate the shaft 28. Shaft 28 also may be
connected to a load 30, such as a generator, a propeller, a
transmission, or a drive system, among others. After flowing
through the turbine 26, the hot combustion gases 18 may exit the
gas turbine system 10 through an exhaust section 32.
[0021] FIG. 2 is a cross-sectional view of an embodiment of the
combustor 12. The combustor 12 includes fuel nozzles 34 that inject
the gaseous fuel-air mixture into a combustion chamber 36. The
combustion chamber 36 is generally defined by a casing 42, and a
liner 40.
[0022] The fuel nozzles 34 are arranged adjacent to one another to
form a generally circular fuel nozzle assembly 44. According to
certain embodiments, each fuel nozzle 34 has a wedge-shaped cross
section designed to abut a pair of adjacent fuel nozzles 34.
Further, in certain embodiments, each fuel nozzle 34 may be
arranged around a central opening 46. Each fuel nozzle 34 may
extend outward from the central opening 46 in the radial direction
47. Each fuel nozzle 34 includes mixing tubes 48 that mix the
gaseous fuel 14 and air to form a fuel-air mixture that is injected
into the combustion chamber 36. One or more of the fuel nozzles 34
also may include a multi-fuel cartridge 50 that injects liquid fuel
into the combustion chamber 36 and directs gaseous fuel to the
mixing tubes 48. These fuels may be contained under pressure within
the multi-fuel cartridge 50. As discussed further below with
respect to FIG. 3, the mixing tubes 48 may be disposed around the
multi-fuel cartridge 50.
[0023] The fuel nozzles 34 each include a base 52 that secures the
fuel nozzle 34 of the combustor 12. A shell 56 extends between the
base 52 and mixing tube fuel/air plenums 58 in the axial direction
60. The shell 56 generally encloses an air feed plenum 62 (FIG. 3)
that directs air from the compressor through the interior of the
fuel nozzles 34 to the mixing tubes 48, which extend through the
mixing tube fuel/air plenums 58 to a face plate 66. The shell 56
includes openings 64 that allow air flow 43 (FIG. 4) from the
compressor to enter the air feed plenum 62. Within the mixing tube
fuel/air plenums 58, the gaseous fuel may enter the mixing tubes 48
through holes in the sides of the mixing tubes 48 to produce the
fuel-air mixture that flows through the mixing tubes 48 to enter
the combustion chamber 36. The multi-fuel cartridge 50 extends
through the base 52, the air feed plenum 62, and the mixing tube
fuel/air plenums 58 to direct liquid fuel into the combustion
chamber 36 and gaseous fuel into the mixing tubes 48. Within the
combustion chamber 36, the gas and liquid fuel-air mixture is
combusted to produce the hot combustion gases 18. From the
combustion chamber 36, the hot combustion gases 18 flow to the
turbine 26.
[0024] FIG. 3 depicts one of the fuel nozzles 34 sectioned to show
the interior of the fuel nozzle 34. The multi-fuel cartridge 50
extends through an aperture 72 in the base 52, through the air feed
plenum 62, through the fuel plenum 132, and through the air plenum
134 to the face plate 66. The fuel plenum 132 is generally defined
by a fuel plenum plate 74 and the interior plate 136. The air
plenum 134 is generally defined by the interior plate 136 and the
face plate 66. The interior plate 136 is disposed generally
parallel to the fuel plenum plate 74 and the face plate 66 and
divides the interior side of the outer housing, or outer wall, 130
into the fuel plenum 132 and the air plenum 134. An alternative
cooling plate 138 may be disposed adjacent the face plate 66 on its
interior surface. The outer housing, or outer wall, 130 is coupled
to the fuel plenum plate 74, the interior plate 136, and the
cooling and face plates 138, 66, respectively to enclose the fuel
plenum 132 and the air plenum 134. The outer housing 130 may
include a series of air purge holes 140 that direct air into the
air plenum 134. The air from the air plenum 134 then flows through
openings 141 in the cooling plate 138 to provide cooling to the
face plate 66. The air from the air plenum 134 may also flow out of
the fuel nozzle 34 through openings 142 (FIG. 4) between the mixing
tubes and the face plate 66, as shown by arrows 143 (FIG. 4),
thereby providing an aft face cooling air path by purging hot air
and any fuel leaking into the air plenum 134.
[0025] The mixing tubes 48 extend through the fuel plenum 132 and
the air plenum 134 and are mounted in apertures 78 in the fuel
plenum plate 74, apertures 79 in the inner plate 136, and apertures
80 in the face plate 66. The mixing tubes 48 include apertures 82
in the tube walls 84 that allow gaseous fuel from the fuel plenum
132 to enter the mixing tubes 48. Air flow 43 enters the fuel
nozzle 34 through openings 64 in the shell 56, and then flows
through the air feed plenum 62 to enter the ends of the mixing
tubes 48 through the apertures 78 in the fuel plenum plate 74.
Within the mixing tubes 48, the air mixes with fuel that enters the
mixing tubes 48 through the apertures 82 to produce the fuel-air
mixture that is directed into the combustion chamber 36. In
particular, the fuel-air mixture exits the mixing tubes 48 through
the apertures 80 in the face plate 66. In certain embodiments the
air in air plenum 134 may be employed to cool the cooling plate
138, and thereby the face plate 66 which is adjacent to the cooling
plate 138.
[0026] The mixing tubes 48 are disposed radially around the
multi-fuel cartridge 50, which extends through an aperture 88 in
the fuel plenum plate 74, an aperture 89 in the inner plate 136,
and an aperture 90 in the face plate 66. As shown in FIG. 3, the
apertures 88, 89, and 90 are centered within the fuel plenum plate
74, the inner plate 136, and the face plate 66, respectively.
Accordingly, the multi-fuel cartridge 50 extends axially through
the approximate center of the fuel nozzle 34. However, in other
embodiments, the locations of the apertures 88, 89, and 90 may vary
to dispose the multi-fuel cartridge 50 in other positions within
the fuel nozzle 34.
[0027] The multi-fuel cartridge 50 includes an inner tube 92 that
defines an inner liquid fuel passage, or compartment, 94, and an
outer tube, or wall, 100 that defines a gaseous fuel passage, or
compartment, 102. According to certain embodiments, liquid fuel,
water, and air, such as high-pressure atomizing air, may be
supplied to the inner fuel compartment 94 of the multi-fuel
cartridge 50 through inlets in the multi-fuel cartridge 50 that are
external to the fuel nozzle 34. The multi-fuel cartridge 50 also
includes a nozzle portion 104 that expels, or sprays, the liquid
fuel which may include water and/or air, from the inner passage 94
through the face plate 66 into the combustion chamber 36 (FIG. 4).
As shown, the multi-fuel cartridge 50 includes at least two
concentric tubes, or interior walls, 92 and 100 that define two
separate compartments 94 and 102, respectively, whose contents may
be pressurized. In other embodiments, any number of one or more
tubes, or walls, may be included within the multi-fuel cartridge
50. For example, in certain embodiments, the multi-fuel cartridge
50 may include an additional tube that defines a passage to
separately supply water or air, or a combination thereof, to the
combustion zone.
[0028] The multi-fuel cartridge 50 is disposed within a mounting
tube 106, which also serves as the inner wall of the fuel nozzle
34, that extends through the fuel plenum 132 and the air plenum 134
and is mounted within the aperture 88 in the fuel plenum plate 74,
aperture 89 in the inner plate 136, and the aperture 90 in the face
plate 66. The mounting tube 106 may fit snugly within the apertures
88, 89, and 90 to inhibit the escape of gaseous fuel through the
apertures 88, 89, and 90. The mounting tube 106 may include a lip
110 designed to assist in the insertion of the multi-fuel cartridge
into the mounting tube 106. In some embodiments, the mounting tube
106 may fit snugly around the outer tube 100 of the multi-fuel
cartridge 50. In some embodiments, the inside diameter of the
mounting tube 106 may be slightly greater than the outside diameter
of the multi-fuel cartridge 50 to allow interoperation with lip
seals mounted to the outer wall 100 of the multi-fuel cartridge 50,
as will now be described.
[0029] FIG. 4 is a cross-sectional view of an embodiment of a fuel
nozzle 34 containing a multi-fuel cartridge 50 fully inserted into
the mounting tube 106. The multi-fuel cartridge 50 comprises a pair
of annular lip seals including a first lip seal 154 and a second
lip seal 156. The lips seals, 154, 156 are made from a thin sheet
of metal, such as aluminum or an Inconel alloy, for example, curled
into a substantially C-shaped cross-section and circumferentially
attached to the outer wall 100 of the multi-fuel cartridge. The
thin cross-section provides a flexible response from the lip seals
154, 156 against the inner wall of the mounting tube 106 when the
multi-fuel cartridge 50 is inserted therein. The first lip seal 154
is seated against a first seal retention projection 158 which is
formed on the inner wall of the mounting tube 106. The second lip
seal 156 is seated against a second seal retention projection 160
which is also formed on the inner wall of the mounting tube 106.
The seal retention projections 158, 160 include a curvature
preferably contoured similar to the curvature of the corresponding
lip seal 154, 156 to help provide a gas tight seal between the
multi-fuel cartridge and the inner wall of the mounting tube 106
when the lip seals 154, 156 physically contact the seal retention
projections 158, 160. The first lip seal 154 may include a smaller
diameter than second lip seal 156 to allow easier insertion of the
multi-fuel cartridge 50 into the mounting tube 106, in particular,
to allow the first lip seal to more easily bypass the seal
retention projection 160 without substantial interference
therewith, thereby avoiding excessive wear that might otherwise
result. The multi-fuel cartridge 50 may be inserted into mounting
tub 106 via aperture 72 of the base 52, then through the lip 110 of
the mounting tube 106 until the cartridge nozzle 104 is seated in
face plate 66 aperture 90, and the first and second lip seals 154,
156 each abut their corresponding seal retention projections 158,
160. The multi-fuel cartridge 50 may also be removed from the
mounting tube 106 in a reverse fashion. This breach loading
capability of the multi-fuel cartridge allows easy inspection of
the interior of the fuel nozzle 34 using, for example, a boroscope
inserted through aperture 72 of the base 52 when the multi-fuel
cartridge 50 is removed. The outer wall 100 and the inner wall 92
of the multi-fuel cartridge 50, and the mounting tube 106, each
comprise a substantially circular cross-section disposed
substantially concentrically about multi-fuel cartridge axis
159.
[0030] The cartridge nozzle 104 is in fluid communication with the
inner compartment 94 to expel liquid fuel from the inner
compartment 94 into the combustion chamber 36. As described above,
the liquid fuel 14 may include light or heavy distillate oil,
naphtha, crude oil, residual oil, or a combination thereof, and
water and/or air. In one embodiment, the liquid fuel comprises an
emulsion of fuel oil and water. When the multi-fuel cartridge 50 is
fully inserted into the mounting tube 106, the cartridge nozzle 104
is disposed in aperture 90 of the face plate 66. The cartridge
nozzle 104 may comprise an atomizing rotating air swirler 105, with
an annular ridge to assist insertion and fit of the cartridge
nozzle 104 into the aperture 90.
[0031] The mounting tube 106 includes several openings forming fuel
plenum inlets 150 between the interior of the mounting tube 106 and
the fuel plenum 132. The fuel plenum inlets are formed in the
mounting tube between the fuel plenum plate 74 and the inner plate
136. The multi-fuel cartridge 50 includes several openings through
its outer wall 100 forming gaseous fuel outlets 152 corresponding
to, and axially aligned with, the fuel plenum inlets 150. Thus,
gaseous fuel 14 in the outer passage 102 of multi-fuel cartridge 50
is in fluid communication with the fuel plenum 132 via the gaseous
fuel outlets 152 and the fuel plenum inlets 150, and may be
delivered therethrough along a fuel flow path as indicated by
arrows 153. The gaseous fuel outlets 152 may be selectively sized
to control a magnitude of gaseous fuel differential pressure across
apertures 82 for controlling fuel injection therethrough to
optimize fuel mixing in the mixing tubes 48. The lips seals 154,
156 are disposed in a gas tight fashion on either side of the
axially aligned fuel plenum inlets 150 and the gaseous fuel outlets
152 and between the outer wall of the multi-fuel cartridge 50 and
the inner wall of the mounting tube 106 to secure passage of fuel
into the gaseous fuel plenum 132 and to substantially prevent
unnecessary dilution or leakage of the gaseous fuel.
[0032] FIG. 5 is a cross-sectional view of an embodiment of the
fuel nozzle 34 containing a multi-fuel cartridge 50 fully inserted
into the mounting tube 106. This embodiment is identical in all
respects to the embodiment as shown in FIG. 4 except that the
second annular lip seal 156 now faces in an opposite direction and
its corresponding retention projection 160 is positioned on the
side of the second lip seal 156 away from gaseous fuel outlets 152.
The seal retention projection 160 includes a curvature preferably
contoured similar to the curvature of the corresponding lip seal
156, as before, to help provide a gas tight seal between the
multi-fuel cartridge and the inner wall of the mounting tube 106.
This embodiment may be advantageous in applications wherein high
gaseous fuel pressure is required because the higher fuel pressure
expands the lip seals 154, 156 so that their outer surfaces press
against the retention projections 158, 160 to form a gas tight
seal, and so are better positioned to channel the fuel through the
gaseous fuel outlets 152.
[0033] When fully assembled, the fueling system provided by the
multi-fuel cartridge 50 delivers liquid and gaseous fuel 14
simultaneously to combustion chamber 36 using one cartridge in a
simplified design. The air feed plenum 62 is kept uncluttered by
other tubes typically required to provide fuel passages to the fuel
plenum 132, thereby avoiding wakes in the air flow and other air
flow non-uniformities that might disrupt air delivery to the fuel
nozzle 34. The breach loading feature of the multi-fuel cartridge
system further simplifies inspection by providing access to the
interior of the fuel nozzle using visual inspection tools such as
boroscopes.
[0034] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to practice the invention, including making and
using any devices or systems and performing any incorporated
methods. The patentable scope of the invention is defined by the
claims, and may include other examples that occur to those skilled
in the art. Such other examples are intended to be within the scope
of the claims if they have structural elements that do not differ
from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from
the literal language of the claims.
* * * * *